The present invention relates generally to the medical arts, and more particularly to a needleless injection site for use in relation to intravenous infusions.
It is common medical practice to intravenously infuse various fluids into the blood vessels of a patient. Such infusion is typically accomplished by the insertion of a hollow introducer needle into a target blood vessel. The introducer needle is fluidly connected to one end of an elongate, flexible tube, the opposite end of which is fluidly connected to a solution bag. The solution bag itself is typically suspended above the patient so as to allow the fluid to flow downwardly through the tubing and into the patient""s blood vessel via the introducer needle which remains operatively positioned therewithin. The fluid tube and solution bag are connected to each other via a metering apparatus which controls the infusion rate of fluid from the bag into the tube.
In many intravenous infusion assemblies, an injection site is fluidly coupled within the tubing intermediate the introducer needle and the solution bag. The injection site typically has a Y-shaped configuration and comprises a tubular main body portion having a tubular side arm portion in fluid communication therewith. The distal end of the side arm portion is fluidly connected to the solution bag via an upper segment of the tubing, with the bottom end of the main body portion being fluidly connected to the introducer needle via a lower segment of the tubing. The top end of the main body portion is itself covered by a diaphragm which is typically fabricated from rubber or a similar resilient material.
The inclusion of the injection site within the tubing allows various medications to be selectively infused into the blood vessel of the patient by the addition thereof to the solution flowing from the solution bag into the blood vessel via the upper tubing segment, injection site, lower tubing segment and introducer needle. This supplemental infusion is typically accomplished through the utilization of a conventional syringe, the needle of which pierces and is extended through the diaphragm disposed on the top end of the main body portion of the injection site. Subsequent to the expulsion of the medication from within the syringe and into the flowing solution, the needle is retracted out of the main body portion of the injection site, with the aperture created in the diaphragm due to the passage of the needle therethrough being substantially closed upon such retraction due to the resiliency of the diaphragm. As will be recognized, the incorporation of the injection site within the tubing allows various medications to be intravenously administered to the patient through the existing infusion site within the blood vessel, thus eliminating the need to subject the patient to additional needle sticks.
Though providing certain benefits to the patient, the injection sites constructed in accordance with the prior art possess certain deficiencies which detract from their overall utility. As previously explained, the use of such injection sites typically requires that the needle of a conventional syringe be extended through (i.e., puncture) the diaphragm attached to the top end of the main body portion of the injection site. However, the necessity of having to utilize a syringe with a needle to facilitate the introduction of the medication into the solution flow is undesirable due to the risk of inadvertent needle sticks. In recognition of this deficiency, there has also been developed in the prior art needleless injection sites which incorporate a diaphragm adapted to assume open and closed configurations without having a needle inserted thereinto. Though these needleless injection sites eliminate the need of having to puncture the diaphragm with a needle, they also possess certain deficiencies which detract from their overall utility. Foremost of these deficiencies is the difficulty associated with disinfecting the injection site, and in particular the diaphragm thereof, subsequent to medication being infused thereinto. In this respect, after each use of the injection site the diaphragm must be cleaned, with such cleaning typically being accomplished through the application of alcohol or a similar disinfecting substance thereto. However, due to the configuration of the diaphragm, complete and effective disinfection thereof is often difficult to achieve, thus increasing the risk of the introduction of contaminates into the solution stream upon subsequent uses of the injection site. The present invention is adapted to overcome these and other deficiencies associated with prior art injection sites.
In accordance with a first embodiment of the present invention, there is provided a needleless injection site comprising a housing. The housing itself comprises a main body portion defining proximal and distal ends, and a bore extending axially therethrough. The housing further comprises a tubular side arm portion which is in fluid communication with the main body portion.
Attached to the proximal end of the main body portion is a reseal member which extends into the bore and includes an elastically openable and closable aperture formed therein. The reseal member normally resides in a closed position wherein the aperture is in a closed configuration. In the first embodiment, the reseal member is deformable such that the application of distally pressure thereto will cause it to distally advance within the bore to an open position wherein the aperture assumes an open configuration. Conversely, the removal of the distally directed pressure from the reseal member will cause it to resiliently return to the closed position wherein the aperture assumes the closed configuration.
The reseal member is preferably fabricated from silicone and comprises a circularly configured proximal portion which defines a top surface and has a flange formed about the periphery thereof for attaching the reseal member to the main body portion of the housing. The reseal member further comprises a cylindrically configured central portion which defines a side surface and a bottom surface having a conically shaped notch formed therein. The aperture extends from the top surface of the proximal portion to the apex of the notch. In addition to the proximal and central portions, the reseal member includes a tubular distal portion which is invertible and adapted to overlap the side surface of the central portion and apply a radially inward biasing force thereto when inverted which maintains the aperture in the closed configuration when no distally directed pressure is applied to the top surface of the proximal portion.
The injection site of the first embodiment further comprises a lock ring for securing the reseal member to the proximal end of the main body portion. In this respect, the flange of the reseal member is rigidly captured between the main body portion and the lock ring. Additionally, formed on the outer surface of the main body portion adjacent the proximal end thereof are Luer threads.
In accordance with a second embodiment of the present invention, there is provided a needleless injection site comprising a housing which also comprises a main body portion defining proximal and distal ends and a bore extending axially therethrough. Formed on the proximal end of the main body portion and extending axially therefrom is an elongate dilator projection. The dilator projection defines a longitudinally extending fluid passage which is in fluid communication with the bore. Attached to the proximal end of the main body portion is a connector cap which defines a central opening into which the dilator projection extends. The housing further comprises a tubular side arm portion which is in fluid communication with the main body portion.
Disposed within the opening of the connector cap is a reseal member which has an elastically openable and closable aperture formed therein, and normally resides in a closed position wherein the aperture is in a closed configuration. The dilator projection of the housing extends into the reseal member. The reseal member is deformable such that the application of distally directed pressure thereto will cause it to distally advance within the opening to an open position wherein the aperture is forced over a portion of the dilator projection. Conversely, the removal of the distally directed pressure from the reseal member will cause it to resiliently return to the closed position wherein the aperture assumes the closed configuration.
In the second embodiment, the reseal member is attached to the connector cap and comprises a circularly configured proximal portion which defines a top surface and has a flange formed about the periphery thereof for attaching the reseal member to the connector cap. The reseal member further comprises a cylindrically configured central portion which defines a side surface and a bottom surface having an elongate, generally concave recess formed herein which is sized and configured to receive the dilator projection. The aperture extends from the top surface of the proximal portion to the apex of the recess. In addition to the proximal and central portions, the reseal member includes a tubular distal portion which is invertible and adapted to overlap the side surface of the central portion and apply a radially inward biasing force thereto when inverted which maintains the aperture in the closed configuration when no distally directed pressure is applied to the top surface of the proximal portion. Like the reseal member previously described in relation to the first embodiment, the reseal member constructed in accordance with the second embodiment is preferably fabricated from silicone. Additionally, the reseal member is preferably cooperatively engaged to the dilator projection and disposed in abutting contact with the proximal end of the main body portion.
The connector cap of the housing includes Luer threads formed on the outer surface thereof adjacent the central opening. Additionally, the main body portion of the housing normally resides in a first position within the connector cap, and is adapted to move distally relative the connector cap to a second position therewithin when distally directed pressure is applied to the reseal member. The removal of the distally directed pressure from the reseal member causes the main body portion to resiliently return to the first position. The main body portion preferably includes a leaf spring molded thereon which is cooperatively engaged to the connector cap and adapted to bias the main body portion to the first position.
In accordance with a third embodiment of the present invention, there is provided a needleless injection site comprising a housing. The housing itself comprises an adapter member defining proximal and distal ends, and an interior chamber. Formed on the proximal end of the adapter member is an elongate dilator projection which defines a proximal portion extending axially from the proximal end, a distal portion extending axially into the interior chamber, and a longitudinally extending fluid passage in fluid communication with the interior chamber. Attached to the adapter member is a connector cap which defines a central opening. The adapter member is disposed within the connector cap, with the proximal portion of the dilator projection extending into the opening thereof.
Disposed within the opening is a reseal member which has an elastically openable and closeable aperture formed therein, and normally resides in the closed position wherein the aperture is in a closed configuration. The proximal portion of the dilator projection extends into the reseal member. The reseal member is deformable such that the application of distally directed pressure thereto will cause it to distally advance within the opening to an open position wherein the aperture is forced over the proximal portion of the dilator projection. Conversely, the removal of the distally directed pressure from the reseal member will cause it to resiliently return to the closed position wherein the aperture assumes the closed configuration. The reseal member, which is also preferably fabricated from silicone, comprises a tubular proximal portion and a cylindrically configured distal portion defining top, bottom and side surfaces, and including an elongate, generally concave recess formed in the bottom surface thereof which is sized and configured to receive the proximal portion of the dilator projection. The aperture extends from the top surface of the distal portion to the apex of the recess. The proximal portion is invertible and adapted to overlap the side surface of the distal portion and apply a radially inward biasing force thereto when inverted which maintains the aperture in the closed configuration when no distally directed pressure is applied to the top surface of the distal portion. The reseal member is preferably cooperatively engaged to the proximal portion of the dilator projection and disposed in abutting contact with the proximal end of the adapter member.
The connector cap of the housing constructed in accordance with the third embodiment also includes Luer threads formed on the outer surface thereof adjacent the central opening. Additionally, the adapter member normally resides in a first position within the connector cap, and is adapted to move distally relative the connector cap to a second position therewithin when distally directed pressure is applied to the reseal member. When the distally directed pressure is removed from the reseal member, the adapter member resiliently returns to the first position. The adapter member preferably includes a leaf spring molded thereon which is cooperatively engaged to the connector cap and adapted to bias the adapter member to the first position.
In the third embodiment, the distal portion of the dilator projection has a tapered outer surface for facilitating the connection of the adapter member and hence the housing to a tubular fluid line. In particular, the housing is connected to the fluid line via the insertion of the distal portion of the dilator projection into the lumen of the fluid line, with the distal portion being frictionally retained within the lumen subsequent to being inserted thereinto.
The adapter member further comprises a tubular adapter sleeve which is slidably extensible over and frictionally maintainable on the distal portion of the dilator projection for facilitating the connection of the housing to a Luer connector. The housing is connected to the Luer connector via the insertion of the adapter sleeve into the lumen of the Luer connector. The distal portion of the dilator projection preferably has a tapered outer surface, with the adapter sleeve preferably having a tapered bore extending longitudinally therethrough which is complimentary to the outer surface of the distal portion of the dilator projection, thus facilitating the frictional retention of the adapter sleeve thereon. Additionally, the distal portion of the dilator projection preferably includes an elongate rib formed on the outer surface thereof, with the bore of the adapter sleeve defining an elongate slot therewithin which is sized and configured to receive the rib when the adapter sleeve is slidably advanced over the distal portion of the dilator projection. The receipt of the rib into the slot is operable to prevent the rotation of the adapter sleeve upon the distal portion of the dilator projection. Further, the adapter sleeve preferably has a tapered outer surface for frictionally retaining the adapter sleeve within the lumen of the Luer connector subsequent to being inserted thereinto.
The adapter member of the housing further defines a tubular lock region within the distal end thereof which is configured to engage the Luer threads of the Luer connector when the adapter sleeve is inserted into the lumen thereof. The lock region preferably defines a plurality of Luer thread pitch barbs therewithin which engage the Luer threads. The lock region of the adapter member is also used to facilitate the connection of the housing to a Y-injection site. In particular, the housing is connected to the Y-injection site via the insertion of the Y-injection site into the lock region of the adapter member, and the extension of the distal portion of the dilator projection thereinto. In the third embodiment, the adapter member preferably comprises an upper section defines the dilator projection, and a lower section which is rigidly attached to the upper section and defines the lock region, with the upper and lower sections defining the interior chamber when attached to each other.
Further in accordance with the present invention, there is provided a method of fabricating a reseal member for use in a needleless injection site. The method comprises the step of molding the reseal member to include a circularly configured proximal portion, a cylindrically configured central portion having an opening formed in the bottom surface thereof, an aperture extending from the top surface of the proximal portion to the opening, and a tubular distal portion. The method further comprises the step of inverting the distal portion in a manner causing it to overlap the side surface of the central portion and apply a radially inward biasing force thereto which maintains the aperture in a closed configuration. The method may further comprise the step of forming a flange about the periphery of the proximal portion. The opening formed within the central portion may comprise a conically-shaped notch, with the aperture extending from the top surface of the proximal portion to the apex of the notch. Alternatively, the opening may comprise an elongate, concave recess, with the aperture extending from the top surface of the proximal portion to the apex of the recess.
There is also provided a method of fabricating a reseal member for use in a needleless injection site which comprises the step of molding the reseal member to include a tubular proximal portion, a cylindrically configured distal portion having a concave recess formed in the bottom surface thereof, and an aperture extending from the top surface of the distal portion to the apex of the recess. The method further includes the step of inverting the proximal portion in a manner causing it to overlap the side surface of the distal-portion and apply a radially inward biasing force thereto which maintains the aperture in a closed configuration.